> if you are going to teraform something venus is much better in the long
run
> its gravity is very close to earths

The run would be very very long.
Terraforming of Venus has been examined at length (as may well be imagined).
The problems are intractably hard in the foreseeable future.
Too much of the wrong sort of material (or conversely too little of the
right sort).
Massive existent temperatures and pressures and no known processes to deal
with the atmosphere.
Adjustment of albedo alone (or functionally equivalent actions) - even to
extreme limits (large sunshield ?) is far from sufficient.
Initial practising must be done on Mars :-)

Sagan wrote some useful populist stuff on this and I'm absolutely sure
Google will have lots to say about it.

        Russell McMahon

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